Abstract: Objective To develop a self-made inoculator for establishing orthotopic transplantable colorectal cancer in mice. Methods An inoculator for establishing orthotopic transplantable colorectal cancer in mice was designed and made. The inoculator was used for inoculating 1×10⁶ H22 cells into colorectal site of each KM mice, and the tumor formation and metastasis was observed. Result Orthotopic transplanted H22 cells to colorectal site of Kunming mice, the tumor formation rate was 100%, the tumor metastasis rate was 33.3%, and the average lifetime of the mice was 16.5±4.5 d. Conclusion The self-made inoculator could be successfully used for establishing orthotopic transplantable colorectal cancer in mice. The operation was convenient, and the tumor formation rate was high.

Key words: Colorectal cancer, Orthotopic transplant, Animal model